With the rise of the Internet and the use of e-mail, electronic communication has the potential to transform the culture of medicine, the physician-patient relationship, and the delivery of preventive health care. Minorities and people in lower socioeconomic groups are accessing the Internet and e-mail through public libraries. Many seek health information. These changes bring new possibilities to the delivery of preventive health care, especially when coupled with encryption technology and an electronic medical record. Instead of generating reminders by computer and mailing them to patients when their next screening appointment is due, we can electronically mail a reminder with personal information directly from the electronic medical record to patients at home, at work, or at the public library. Additionally, we can customize educational information that we deliver at an individual level. We can adapt "mass customization," a model developed by electronic businesses, to deliver customized information about screening to individual patients on a mass market scale. In this proposal we will use the example of colorectal cancer screening to demonstrate these possibilities. Personal information from the electronic medical record and customized educational information about colorectal cancer screening will be delivered to patients through an interactive Internet letter called the "NetLET." We aim to: 1) develop the electronic intervention called the NetLET (interNet LETter) and to demonstrate that it can be feasibly implemented with physicians and patients in a primary care internal medicine practice and city public library system; 2) conduct a pilot evaluation of the NetLET'S effect on adherence to colorectal cancer screening guidelines compared to a standard mailed letter to inform the design of a future randomized controlled trial; 3) Assess the effect of the NetLET on interest in and knowledge about colorectal cancer screening compared to a standard mailed letter to inform the design of a future large clinical trial. This study will recruit 220 patients and randomize them into intervention and control groups, stratified by gender 'private' (eg. home, work) or 'public' access to e-mail. 'Public' access will be through the Houston Public Library System and the Harris County Public Library systems. Patients in the intervention group will receive the NetLET; patients in the control, a customized personal letter by mail. This pilot study will assess the effect of the NetLET on colorectal cancer screening compliance and will determine barriers to 'public' access to the intervention. This proposal will lead to studies that will examine how electronic interventions can promote informed decision-making and deliver preventive health care in ways that strengthen the generalist physician-patient relationship.